Phases types

Nonpolar organic mobile phases, such as hexane with ethanol or 2-propanol as typical polar modifiers, are most commonly used with these types of phases. Under these conditions, retention seems to foUow normal phase-type behavior (eg, increased mobile phase polarity produces decreased retention). The normal mobile-phase components only weakly interact with the stationary phase and are easily displaced by the chiral analytes thereby promoting enantiospecific interactions. Some of the Pirkle-types of phases have also been used, to a lesser extent, in the reversed phase mode. 

Although they are termed homogeneous, most industrial gas-phase reactions take place in contact with solids, either the vessel wall or particles as heat carriers or catalysts. With catalysts, mass diffusional resistances are present with inert solids, the only complication is with heat transfer. A few of the reactions in Table 23-1 are gas-phase type, mostly catalytic. Usually a system of industrial interest is liquefiea to take advantage of the higher rates of liquid reactions, or to utihze liquid homogeneous cat ysts, or simply to keep equipment size down. In this section, some important noncatalytic gas reactions are described. 

Type Eduet Derivatizing Agent number type Stationary phase type of binding or reaetion... 

This strategy is the one most commonly used for the analytical determination of ena-tiopurity. A given racemate is reacted with a unichiral derivatizing agent, and the resulting pair of diastereomers is separated on an achiral stationary phase, in most of the cases on a reversed-phase type (Fig. 7-2). 

Phase Type in Struk-turbericht Character Atoms per unit cell (mini mum) 0 B2 and Z,20 body- centered cubic 2 /3-Mn A13 complex cubic 20 7 D81, 82, 83 84 complex cubic 52 e hexagonal close packed, c/a <(8/3) 2 ... 

In the solid phase type of separation the antibody or binding protein is bound to an inert material such as Sephadex or glass beads yet is still free to react with the ligand. 

A large range of stationary phases is available, and according to their polarity they can be divided into normal phase and reversed phase types. Silica gel, aluminium oxide, and a nitrile-bonded-phase are normal adsorbents used to separate carotenoids... 

Because the main point of interest is the stability of an emulsion, a series of phase-type diagrams could be plotted. A hypothetical diagram could have as its ordinate the temperature of mixing and as its abscissa the rate of mixing. A line could be drawn on this diagram indicating that above any given... 

Silica and alunlna with reversed-phase type mobile phases... 

Choice of phase type Phase weight Particle size pH of sample Dilution of sample... 

The cubic phases with Somatostatin were allowed to swell to the water swelling limit, while the Desmopressin preparations were of the lamellar phase type, i.e. with low water content, and were therefore assumed to swell in vivo. Approximately 0.5 g of either cubic or lamellar phase was injected, corresponding to 2.5-3.0 mg peptide per kg body weight. 

On the basis of different assumptions about the nature of the fluid and solid flow within each phase and between phases as well as about the extent of mixing within each phase, it is possible to develop many different mathematical models of the two phase type. Pyle (119), Rowe (120), and Grace (121) have critically reviewed models of these types. Treatment of these models is clearly beyond the scope of this text. In many cases insufficient data exist to provide critical tests of model validity. This situation is especially true of large scale reactors that are the systems of greatest interest from industry s point of view. The student should understand, however, that there is an ongoing effort to develop mathematical models of fluidized bed reactors that will be useful for design purposes. Our current... 

Breathing-related sleep disorder Circadian rhythm sleep disorder Delayed sleep phase type Jet lag type Shift work type Unspecified type... 

Name of Chromatography Stationary Phase Mobile Phase Types of Compounds Amenable to Separation... 

Table 3.9. A sublattice model suggested for the main Laves phase types.

El Dorado Engineering recommended that the M28 propellant (which is similar to M-9 propellant) not be pumped or handled or allowed to settle in concentrations above 40 percent by weight in water (EDE, 2001b). In this way, inadvertent initiation of detonations would be prevented, and no nondetonation-to-detonation, transition-phase-type reactions would occur in the process if the slurries were shocked. 

Waste type Solid phase type Model isotherm Y axis Intercept Slope X axis R2... 

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